This invention relates to the autotransfusion of blood during surgical procedures.
By the autotransfusion of blood is meant collecting blood from a bleeding wound and transfusing it into the circulatory system of the same patient from whom it was removed.
Suitable apparatus and techniques for carrying out autotransfusions presently are not available for application in routine surgery. As a consequence, it is conventional practice for the surgeon or his assistants to soak up the blood in the wound with surgical sponges which thereafter are discarded. The sponges are counted before and after each operation, to insure against one being left and subsequently sewn up in the wound.
This procedure has obvious and significant disadvantages. It wastes the patient's blood. It requires typing the patient's blood. In many cases transfusions are necessary, requiring drawing on the hospital's supply of blood bank blood. This not only depletes the hospital's store of blood, but also adds an additional element of cost to the operation. Furthermore, in transfusions involving blood bank blood there is alway the danger of detrimental reaction caused by mismatching of blood types or other factors.
Also, present procedures place an added responsibility on the surgeon and his staff in that they are required to handle and keep track of the sponges applied to the wound.
Although autotransfusing the patient's own blood during the course of a surgical operation would provide a solution to the foregoing problems, this technique presently is not practiced widely because of serious inherent difficulties.
The patient's blood tends to clot as soon as it is withdrawn from the body and in its clotted form is not suitable for autotransfusion. It is difficult to control the clotting by the addition of heparin or other anti-clotting agents because the blood is to be reintroduced into the same patient from whom it was withdrawn. If too little heparin is added, the blood will clot. If too much heparin is added, the entire blood content of his body will be anti-coagulated so that the wound will not stop bleeding.
Furthermore, it is difficult to meter both the correct amount of anticoagulant added to the blood as it is withdrawn from the wound, and the anticoagulant-treated blood returned to the patient's circulatory system, with sufficient precision to make the autotransfusion procedure of practical application.
Still further, it is difficult to remove the blood from the wound without drying it out, or foaming it, or otherwise altering it so that it becomes unsuitable for reintroduction into the blood stream of the patient.
It accordingly is the general object of the present invention to provide method and apparatus for autotransfusing blood which overcomes the foregoing problems and provides a means for autotransfusing blood routinely during surgical operations, safely, with accurate control, without damaging the blood, and without requiring the use of highly skilled personnel or complicated and expensive equipment.
It is another object of the invention to provide blood autotransfusing apparatus in a form which may be sold commercially in aseptic condition at a cost so low as to make it economically possible to use the apparatus a single time only, as a disposable item.